THE VILLAGES, Fla. — In a speech that appeared intended to quell doubts among seniors about his proposal to overhaul Medicare, Republican vice presidential candidate Paul Ryan took a deeply personal approach Saturday morning in describing what he and Mitt Romney have in mind for the health insurance program for the elderly and the disabled.

Taking the stage with his 78-year-old mother at this sprawling central Florida retirement community, Ryan told the crowd stories of his family as he made the case that he and Romney would not change the benefits of current seniors. He offered few specifics about his own plan but went into the greatest detail yet in hammering President Obama on the issue.

“Our plan does not affect the benefits for people who are in or near retirement,” Ryan told the several hundred senior citizens gathered around a gazebo. “It’s a promise that was made, and it’s a promise that must be kept. But in order to make sure we can guarantee that promise for my mom’s generation, for those baby boomers that are retiring every day, we must reform it for my generation.”

There was no mistaking the reason for Ryan’s visit to this 60,000-person retirement community, referred to by residents as “Disney World for older people” — a place where retirees speed around in golf carts and enjoy daily entertainment programs.

A huge sign reading “Protect & Strengthen Medicare” was hung behind the podium, the first time the word “Medicare” has shown up on a campaign sign in the week since Ryan was tapped to serve as Romney’s running mate.

And several times during his speech, he took the hand of his mother, Betty Douglas, a former interior designer and a part-time resident of Lauderdale-by-the-Sea, four hours away in south Florida.

“This is my mom, Betty. She’s why I’m here. She and her grandkids are why I’m here,” Ryan said as he introduced his mother, clad in a bright yellow top and white capris, to the crowd. The candidate wore a dark-blue, short-sleeved polo shirt.

Seniors made up nearly a quarter of all Florida voters in the 2008 general election, and they represent a key group that Romney and Ryan will have to woo if they are to win the battleground state — and other senior-heavy states — this fall.

Ryan’s speech Saturday marked the first time the GOP ticket has made a major push to go on offense against on the Medicare issue. For his first few days as Romney’s running mate, Ryan made no mention of the program on the trail, and even after he began bringing up the issue toward the middle of this week, he took aim at Obama and largely steered clear of discussing his own proposals.

In his remarks here, Ryan sought to draw a sharp contrast between the GOP ticket and Obama’s. He still spent more time targeting Obama than describing the details of his own plan, however, arguing broadly that “the best way to reform Medicare is to empower 50 million seniors” rather than a board of “15 unelected bureaucrats,” a reference to a component of the new national health-care law.

He told the crowd that “one out of six of our hospitals and our nursing homes will go out of business” and that 4 million seniors would lose their Medicare Advantage coverage as a result of the $716 billion in Medicare savings enacted over the next decade through the new law — cuts that are a part of the Ryan budget blueprint but that he and Romney now say they would work to undo.

A budget wonk known for giving PowerPoint presentations at town hall meetings, Ryan took a different tack Saturday, seeking to make his case in personal terms. He told the crowd that “like a lot of Americans, when I think about Medicare, it’s not just a program. It’s not just a bunch of numbers. It’s what my mom relies on. It’s what my grandma had.”

Ryan also spoke for the first time on the trail about his grandmother, who he said had advanced Alzheimer’s disease and had moved in with him and his mother while Ryan was in high school.

“You learn a lot about life” when a relative falls ill, he said.

“Medicare was there for our family, for my grandma, when we needed it then, and Medicare is there for my mom while she needs it now, and we have to keep that guarantee,” he said to applause.

He also emphasized another point Republicans have made on the trail in recent weeks, citing his mother in a dig at Obama’s now-infamous “you didn’t build that” line.

“Mom, I am proud of you for going out and getting another degree,” Ryan said. “I’m proud of you for going out and building the small business that you created, and mom, you did build that.”

Whether the GOP ticket’s effort to seize the offense in the Medicare debate will pay dividends among voters remains an open question. Democrats were ready with their own message Saturday morning: Spotted flying above The Villages was a plane, sponsored by MoveOn.org, bearing a banner reading, “Paul Ryan, Keep Your Hands Off Our Medicare.”

In a statement, Obama campaign spokesman Danny Kanner said that Ryan was “not telling the truth” about his Medicare plan and that he had left out key, “politically ‘suicidal’ ” details.

“Congressman Ryan didn’t tell seniors in Florida today that if he had his way, seniors would face higher Medicare premiums and prescription drug costs and would be forced to pay out of pocket for preventive care,” Kanner said. “He didn’t say that if he had his way, Medicare would be bankrupt in just four years or that he would give $150 billion taxpayer dollars back to private insurance companies, which raises costs for everyone.

“He didn’t say that they’d turn Medicare into a voucher system, ending the Medicare guarantee and raising costs by $6,400 a year for seniors,” he added. “And he certainly didn’t say that they’d do it all to pay for tax cuts for millionaires and billionaires. But those are the facts, and the ‘substantive’ debate he claims they want requires Romney and Ryan to be honest about them.”

Opinions voiced by those in the audience — like the level of detail when it came to their knowledge of Ryan’s Medicare plan — were mixed.

Bill Coale, a 67-year-old resident of The Villages who came originally from Sterling, Va., said that he hasn’t looked into Ryan’s proposal but that “anything is better than what we’ve got right now,” referring to the national health-care law.

George MacDonald, 73-year-old retiree from Long Island, said he had “no problem” with Ryan’s plan.

“I personally like his plan, because at 73, it really wouldn’t affect me,” he said. “It’s something for the future. . . . Under Obama, I just have too many problems — with the money he took away, the $716 billion.”

But Pat Graybill, a 71-year-old retiree from Ohio who has lived at The Villages since 1981, said that while she hasn’t heard too much about Ryan’s plan, she believes that Medicare shouldn’t be tinkered with.